Knife-sharpening machine



A. vv. RUDOLPH.

KNIFE SHARPENING MACHINE;

FILED DEC.10 1921.

3 f/g/ Wag we.; v y, f: 1 rse 'N reiterated exlan .23, ledit.,

ALFRED WILLAll/ RUDOLPH,

OF ST. LGUIS, MISSOURI.

KNIFE-SHARPENNG TEACHENE.

Application filed December 10, 1921.

To @ZZ w 7mm t may concern Be it known that l, ALFRED YV. RUDOLPH, acitizen of the United States of America, residing at St. Louis, in theState of Missouri, have invented a new and useful Knife-SharpeningMachine, of which the following is a specication.

The prime object of this invention is the provision of a simple,durable, inexpensive and eficient machine by which steel knives may bequickly sharpened throughout the entire length of the blade and in whichthe sharpening material may be quickly replaced when worn.

Referring to the accompany'uig` drawing, wherein like numerals refer tolike parts throughout, Figure 1 is a plan view of one side of themachine as the same appears when suspended upon a wall; Figure 2 a frontelevation depicting` the insertion of a knife between the sharpeninglsurfaces; Figure 3 a plan view which is the reverse of Figure 1; andFigure 4 a sectional view taken along line 1 4 of Figure 1.

1 indicates a wooden block having apertures 2 for the reception of hookswhen the machine iS hung upon a wall, and secured to said block is asubstantially oblong box comprising side-walls 3, front-plate f1-provided with a slot 5 and bottom-plate 6 Ywhich also has a slot 7.

Disposed within said box a reciprmalli," movable plate 8 having adowir-tiuned flange 9 projecting thi-(nigh slot T and lugs 10 adapted toengage springs l1` the latter being` secured to lugs 12 of plate #l andserving to retract plate S after removal of the knife from thesharpening surfaces. The forward edge of plate 8 projects through slot 5of front plate l and is provided with extensions 13 against which thesharpening stones 14- are held by detachable plates 15 secured by screws16. rifhe forward edge of bottom-plate 6 is provided with foursubstantially triangular-shaped extensions 17 which are similar inappearance to scissorblades and the additional set of stones 18 areretained thereagainst by detachable plates 19 (of corresponding shape)fastened by screws 20.

Serial No. 521,413.

An arm 21 pivotally fastened at 2Q to plate -1 serves to support aholder 223 for a pad 2st of absorbent material saturated with oil andthe knife blade is preferably drawn over said pad before and aftersharpening. lV hen the machine is not in use, said arm may be turnedinwardly upon its pivot and a suitable cover (not shown) placed over thewhole.

Finally it should be noted that one set of the sharpening stones may becomparatively coarse so as to prepare the blade for the finishing actionof the other set of less abrasive material, and that, in distinction tocertain other devices of the same general character, the construction ofthis machine is such that the entire length of the knifeedge may besharpened.

1n using the machine the knife blade 25 is inserted within the space A(Figure 1) so as its cutting edge rests against one of the immovablestones affixed to plate 6 and one of the movable stones carried by plate8. rEhe blade is then pressed downward and simu taneously drawn towardthe operator, thereby forcing plate S from left to right against theresistance of springs 11 which serve to return said plate to itsoriginal position immediately upon removal of the blade.

lllhat l claim as new and desire to secure by ,lLetters-llatent is l.,koi'fe-sl'iarpeuer comprising a reciprocally movable member` a pluralityof sharpening stones secured thereto, an irnmovable plate positionedopposite said stones.. and a plurality of similar stones affixed to saidplate, the stones of said mein# ber being spaced apart at their base fid converging at their upper extremities, and the stones of said platebeing juxtaposed at their base and diverging upward, whereby asubstantially 1f-shaped channel is provided between the sets of stonesfor the insertion of a knife-blade.

2. rl. knife-Sharpener comprising a reciprocally movable member, aplurality of sharpening stones secured thereto, an immovable platepositioned opposite said stones and a plurality of similar stones af-

